Sex-Associated Radiographic and Clinical Differences in Nontuberculous Mycobacteria Pulmonary Disease.

The incidence of infections caused by nontuberculous mycobacteria (NTM) are steadily increasing worldwide and the most common site of infection is the lung. Clinical characteristics of individuals with NTM pulmonary disease (NTM-PD) demonstrate pronounced geographical heterogeneity. In the United States, NTM-PD has an affinity for post-menopausal Caucasian females, many of whom are never-smokers, whereas in Asia NTM-PD is more common in males with post-tuberculosis lung disease. While these geographical differences are known on the global scale, it remains unclear whether radiographic sex-associated differences in NTM-PD are present within the US cohort. In this single center cross-sectional retrospective study of our patient registry, we sought to assess this knowledge gap by comparing radiographic and clinical features of individuals with NTM-PD by sex. We observed a significant preponderance of cavitary disease in men, while women commonly presented with bilateral apical fibrosis, increased nodules and tree-in-bud patterns in the lower lobes, and an increased risk of refractory disease and concomitant co-infection. Results from this study demonstrate several sex-associated differences in the radiographic phenotype of NTM-PD, and may be the result of differences in pre-existing risk factors that contribute to the development of NTM-PD. Future studies will be required to better assess the broad applicability of these findings to centers from other geographic regions where the underlying etiology of disease may vary.